Offset cutting edge for scrapers



Jan. 22, 1957 R, F ER 2,778,129

OFFSET CUTTING EDGE FOR SCRAPERS Filed May 16, 1951 2 Sheets-Sheet 1 1 1 fl INVENTOR. l

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Jan. 22, 1957 E. R. FRYER 2,778,129

OFFSET CUTTING FOR SCRAPERS Filed May 16, 1951 2 Sheets-Sheet 2 O O O O O O O O O O 7 INVENTOR.

EDWARD R. FR YER BY United States Patent 2,778,129 OFFSET CUTTHJG EDGE FGR SCRAPERS Edward R. Fryer, Willoughby, Ohio, assignor, by mesue assignments, to General Motors Corporation, Detroit,

'ch., a corporation of Delaware Application May 16, 1951, Serial No. 226,601 7 Claims. (Cl. 37-141) This invention relates to improvements in cutters and cutting edges and more particularly to offset cutting edges for scrapers.

One of the objects of the vide a straight cutting edge or any other desired cutting edge contour. The offset cutting edge can be of the one-side offset or drop-center cutting edge type.

Another object of the in a cutter of the type described a cutter base blades, as set forth above, with the'locating means for the blades consisting of spaced behind and to a side of the first.

Another object of the present invention is to provide forward being in a protruding sec- .tion of the base giving greater blade support for an olfset cutting edge.

Another object of a double edged cutting blade of locating means on than the other.

.edgewearlife.

Another object of the present invention is to provide in a double edged cutting blade, of the type-described and as set forth above, hardened cutting edges, one cutting edge 'being hardened to a wider zone along the cutting edge than the other so that long cutting edge wear life can be obtained.

Other features of my invention reside in the arrange ment and design of the parts for carrying out their appropriate functions.

Other objects and advantages of my invention will be apparent from the accompanying drawings and description and the essential features will be set forth in the appended claims.

In the drawings:

Fig. 1 is a plan View of the component blades arranged on the cutter base to form a drop center scraper cutting edge;

Fig. .2 is a vertical sectional view, enlarged, of the cutter taken along the line 22 of Fig. 1;

base is of the same design.

Fig. 3 is a plan view of one of the blades shown in Figs. 1 and 2;

Fig. 4 is a plan view of a drop center scraper cutting edge, similar to Fig. 1, but having a smaller offset;

Fig. 5 is a plan view of a straight cutting edge formed of the same blades shown in Figs. 1 or 4;

Fig. 6 is a plan view of a one-side .oifset cutting edge;

Fig. 7 is a plan view of amodified form of cutter having component blades arranged on a cutter base .to form a .drop center scraper cutting edge;

Fig. 8 is a vertical sectional View, enlarged, of the cutter taken along the "line 8-8 of Fig.7;

Fig. 9 is a plan view of one of the blades shown in Figs. 7 and 8;

Fig. 10 is a plan view of the blades arranged on the cutter base of the Fig. 7 modification to form a straight cutting edge; while Fig. 11 is a plan view Serial No. 111,496, filed August 20, 1949,

Patent No. 2,674,815 on April 13, 1954.

and a rearwardly spaced leading edge side of the edge 23. This protruding .seen in Fig. l. areless likely to of time.

base, but this between these Each double edged blade 25 mounted on Four blades 25 are shown mounted on the cutterbase in Fig. 1. These blades may be rearranged to :form othertypes of cutting edges as desired. Hence, a separate blade is not needed for each type cutting edge used :in normal Each blade has opposed cutting edges 26 and '27 with the cutting edges being parallel to each other. It should be noted that even though cutting edges .26 and 27 are disthe cutting cutting edge than the other. The variations of width in hardness zone are designed to give the maximum Wear life to each of the edges26 or27 of the blade.

in Fig. 2. Hence, these two different hardness zone widths are directly related to the offset locating holes 32 in the blade and holes 30, 31 in the cutter base, to the variety of scraper cutting edge arrangements shown, and to the amount of cutting edge Wear life obtainable from each edge 26 or 27 of the reversible blades 25 Locating means is provided on the base and on each blade coacting with each other so that either cutting edge of each blade may be presented forwardly in cutting position. A means is also provided to removably attach each blade to said base. Although the locating means and the attaching means might be separate and distinct elements, Figs. 1 to 6 disclose them as a single structure, namely, bolts and bolt holes. This structure consists of holes 30, 31 in the base and holes 32 in the blades, with bolt and nut connections 33 adapted to secure the blades to the base. Locating means or holes 30 are in the protruding middle section 23 of the base while locating means or holes 31 are also in the base but spaced parallel with, behind and to a side of locating means 30. Holes 31 are spaced a distance B behind holes 30. Although the holes 30 and 31 are disclosed as lying in two parallel lines which extend perpendicular to the direction of movement of the cutter, the holes to attach and locate any one blade may extend at a diiferent angle than merely perpendicular to the direction of movement of the cutter.

The locating means or holes 32 in each blade are spaced a given distance closer to one cutting edge than to the other. This distance is equal to the distance between the spaced locating means 31 and 30. In other words, distance C minus D equal B in Figsgl and 3. Also, the distance B is twice as great as the distance that the holes 32 are offset from the transverse center line of the blade 25.

Although the locating means is shown as having holes 30, 31 and 32, this invention contemplates that the cating means may take the form of straight edges, projections or X-shaped slots.

Figs. 1, 4, 5 and 6 illustrate the various types of cutting edge contours obtainable by interchanging blades 25. Fig. 1 illustrates a drop center scraping edge arrangement with the two center blades protruding G distance ahead of the end blades. This arrangement gives the largest overhang or offset in the drop center cutting edge arrangement. In this case, the dimension C (Fig. 3) is toward the front of the two center blades and toward the rear of the two side blades. It is ideal for cutting and loading certain kinds of soils.

Fig. 4 illustrates a drop center cutting edge arrangement with the two center blades protruding H distance ahead of the end blades. Dimension C is toward the front of all four blades. This arrangement gives maximum overhang from all four blades, and thereby maximum wear life is obtained from each cutting edge from all four blades at one setting of the blades. Of course, each of the blades of Fig. 4 could be turned end for end which would still maintain a drop center cutting edge arrangement with an H distance protrusion. The dimension D (Fig. 3) would then be toward the front of each blade. However, this would provide a minimum overhang for each of the four blades. This latter arrangement with minimum overhang is probably best for boulders and rocky soil.

Fig. 5 illustrates a straight cutting edge with all four blades having their cutting edges in a straight line for land leveling and smooth grading, for grading ditches and back slopes and for a level out and a level spread on any earth moving job. This arrangement is also better for loading the scraper bowl in some types of soil. Here, dimension D is toward the front of the center blades and dimension C is toward the front of the side blades.

Fig. 6 discloses a one-side ofiset arrangement. Of

course, either the right or left end blades of the scraper cutting edge may be set back of the remaining three blades even though Fig. 6 discloses only the blade on the right-hand end being set back. This arrangement would be desirable for making the rough scraper cut on a steep side slope.

It has been found that a very practical set of dimensions for this invention are these: A equals 2 inches, B equals 2 inches, C equals 9 inches, D equals 7 inches, E equals 4 inches, F equals 2 /2 inches, G equals 4 inches, H equals 2 inches, and 1 equals 2 inches. Of course, the offsets and these dimensions may be greater or less with wider or narrower blades to secure similar combinations of scraping edges and still utilize the principles outlined here.

The cutter of this invention may be truly termed a universal cutter, since a scraper operator may obtain a wide variety of cutting edges eventhough he uses only one standard type of blade. He can arrange the blades to form the best type of cutting edge for each type of soil condition or job condition that he encounters. A separate blade for each job is not needed. As contrasted with the standard scraper blade, the blades of this invention are cheaper to produce, have a lower maintenance cost and require a smaller investment in inventory for the scraper owner. They are shorter and lighter in weight and, hence, are more easily handled and mounted on the scraper cutter base. If one section breaks in use or if one section wears faster than the others, only this one section needs to be replaced. This replacement procedure is cheaper and faster than heretofore. Of course, the broken or worn section may, if desired, be merely turned end for end and then interchanged with one of the other blades of the cutting edge. Since the operator of the scraper may reverse or turn the blades end for end and may also interchange them, maximum cutting edge wear life is obtained. For instance, side and center blades of Fig. 1 may be reversed and interchanged to give four new cutting edges.

Figs. 7 to 11, inclusive, disclose a second form of this invention called the single offset type. This second form obtains some of the same results of the first form but in a slightly different manner. It also has certain disadvantages over the first form. For example, the center cutting blades are not as well supported.

The cutter base, indicated generally at 20, consists of a front surface 22' rigidly supported by a brace 21'. The front surface does not have a protruding middle section, as found in the first form of the invention disclosed in Figs. 1 to 6. Front surface 22' has a straight leading edge 24'.

The double edged blades 25 are each of the same design and have parallel cutting edges 26 and 27'. As in the first form of the invention, these cutting edges need not be parallel nor have a straight edge.

Each cutting edge has a hardened area 28' or 29. One cutting edge is hardened to a wider'zone along its cutting edge than the other. The difference in width of hardness is indicated by dimensions E and F in Fig. 9. The locating and attaching means or holes 32' in the blade 25 are spaced closer to one cutting edge than the other. The variations of width in hardness zone are designed to give the maximum wear life to each of the edges 26', 27 of the blade. The hardness extends up to approximately the leading edge 24 when the blade is mounted on the cutter base 20', as shown in Fig. 8. In other words, the distances D minus F or C minus E are approximately equalto the distance from the holes 31' to the leading edge 24 in Fig. 8. Hence, these two different hardness zone widths are directly related to the ofiset locating holes 32 in the blade and holes 31' in the cutter base, to the variety of scraper cutting edge arrangements shown, and to the amount of cutting edge wear life obtainable from each edge 26' or 27 of the reversible blades 25'.

Locating means is -provided on the base and "on each edge than tolthe-otlrer, whereby -the "blades may be interblade that coact witheach other whereby eitherl'cu-tting changed andturnedendsfor end "to provide a drop center "edge of each blade may be presented'in cutting position. cutting edge, a straight cutting edge ora one-side otfset A meansis also-provided-to removably attach each blade cutting edge and to provide interchangeability and 'long to the base. Although the attaching means and the lowear life ineach'blade.

eating means may be separate structural elements, they are '3. A cutter comprising a cutter'base, locating means on said disclosed as being all one cooperating structure in Figs. ase extending in a straight line perpendicular to 7 to 11. The means consist of holes 31' in the cutter the direction of movement of said cutter, a plurality of base, holes 32' in the blades, and the bolt and nut unit 33 substantially identical blades including at least three to detachably align the holes together. Of course, the 10 which in end to end relationship equal the length of said locating means need not consist of holes 31' and 32 but base, means to removably attach each blade on said base, may be a locating means of a different sort, for example, each blade being double edged with parallel transverse straight edges, projections, X-shaped slots, etc. The holes cutting edges, a locating means on each blade coacting 31' in the base extend in a straight line perpendicular to with the locating means on said base, said locating means the direction of movement of the cutter. Of course, this being transversely spaced generally vertical apertures, said invention contemplates that the holes needed to mount locating means on each blade being in a single line parallel any one cutter may extend at another angle to the directo a cutting edge and spaced a given distance closer to one tion of movement other than a right angle. cutting edge than to the other, whereby the blades may be The holes 32' in the blades 25 are spaced at given disinterchanged and turned end for end to provide a drop tance closer to one cutting edge than the other. This is center cutting edge, a straight cutting edge or a one-side shown by dimensions C and D in Fig. 9. This spacing offset cutting edge and to provide interchangeability and of the holes determines the olfset of the cutting edge. long wear life in each blade. For example, the distance C minus D of Fig. 9 must be 4. A cutter comprising a cutter base having a forwardly equal to the offset distance G of the cutting edge in protruding section, locating means on said protruding Fig. 7. section extending perpendicular to the direction of move- The single offset type cutting edge also has a wide ment of said cutter, another locating means on said base variety of cutting edge forms. Fig. 7 shows a drop center spaced parallel with, behind and to a side of said first type scraper cutting edge arrangement, similar to Fig. l, locating means, said other locating means being parallel with the two center blades protruding G distance ahead to said locating means on said protruding section, a pluof the end blades. Fig. 10 shows a straight cutting edge 80 rality of blades, means to removably attach each blade on with along overhang to the blades; while Fig. 11 shows said base, each blade being double edged with parallel a straight cutting edge with a shont overhang. This sectransverse cutting edges, a locating means on each blade ond form of the invention may also provide a one-side coacting with one of the locating means on said base, offset arrangement, similar to Fig. 6 in the first modificasaid locating means being transversely spaced generally tion, by merely having either of the two end blades in Fig. vertical apertures, said locating means on each blade 7 reversed. This would provide an offset of G distance being parallel to a cutting edge and spaced a given distance at one end only of the cutting edge. from the transverse centerline of the blade, the distance it has been found in practice that the following dibetween the spaced parallel locating means on the base mensions give satisfactory results with this second form being twice said given distance, whereby the blades may of cutter: C equals 10 inches, D equals 6 inches, E be interchanged and turned end for end to provide a drop equals 5 inches, F equals 2 inches, and G equals 4 inches. center cutting edge, a straight cutting edge or a one-side Of course, the olfsets and these dimensions may be made offset cutting edge and to provide interchangeability and greater or less and could be used with wider or narrower long wear life in each blade. blades to secure similar combinations of scraper cutting 5. An earth cutter for a scraper comprising a cutter edges. base, said cutter base having a forwardly protruding mid- WhatI claim is: dle section, said base having a series of laterally spaced 1. A cutter comprising a cutter base having a forwardly generally vertical holes arranged in two parallel lines protruding section, locating means on said protruding extending perpendicular to the direction of movement of section, another locating means on said base in a zone said cutter, the forwardmost line of said holes being in laterally removed from said section spaced behind and to said protruding section while the rearwardrnost line a Side Of Said first locating means, Said other locating being in said base at each side of said protruding section, means being parallel to said locating means on said proa plurality of blades adapted to be removably attached truding section, a plurality of blades at least one for to said base, each blade being double edged with parallel id t n and One for Said means to removably transverse cutting edges, each blade having a series of a h each blade on Said base, each blade being double laterally spaced generally vertical holes parallel to a cutedged, a locating Ina-ans 011 each blade wading With 0116 ting edge but spaced at given distance from the transverse Of the locating means on said base, said locating means centerline of the blade and adapted to align with same being transversely spaced generally vertical apertures, of the holes in the cutter base, means to attach and align said locating means on each blade being spaced a given each blade to said base by said holes, the distance bedistance 610561 to 0116 Cutting edge than to the other, the 30 tween said two parallel lines being twice said given disdistance in the rearward direction between the spaced tance, whereby the blades may be interchanged and locating means on the base and said given distance being turned end for end to provide a drop center cutting edge, equal, whereby the blades may be interchanged and turned a straight cutting edge or a one-side offset cutting edge end for end to provide various cutting edge contours. and to provide interchangeability and long wear life 2. A cutter comprising a cutter base, locating means in each blade. on said base extending perpendicular to the direction of 6. A cutter as set forth in claim 5, each of the cutting movement of said cutter, a plurality of substantially edges of each double edged blade being hardened, one identical blades including at least three which in end to cutting edge being hardened to a wider zone along the end relationship equal the length of said base, means to cutting edge than the other, said wider hardened zone removably attach each blade on said base, each blade being on that edge of a blade farthest removed from said being double edged with parallel cutting edges, a locating series of holes in said blade.

means on each blade coacting with the locating means on A C t er, 8 s t forth in claim 5, wherein all blades said base, said locating means being transversely spaced are sPtfstantlally ldeflilcal 111 Shape and Size 80 as t generally vertical apertures, said locating means on each Permlt 'mtel'changeablhtyblade being spaced a given distance closer to one cutting (References on following page) 7 8 References Cited in the file of this patent 2,310,396 Clinkscales Feb. 9, 1943 P N 2,329,831 Ferguson Sept. 21, 1943 UNITED STATES ATE T 2,443,492 Austin June 15, 1948 1 Burkenbeuel ly 1 932 2,577,877 Daniels 11, 1951 2,154,503 French et P 18, 1939 5 2 29 945 y l ki Man 3, 1953 2,220,819 Johnson NOV. 5, 1940 

